About 200 people, including many families, picnicked, listened to live music and learnt about beekeeping and gardening at Jubilee Park.
Mornington Community Group member and picnic co-organiser Annika Korsten said the idea for the event came from feedback at a community building seminar.
"People wanted a good old-fashioned picnic to bring the community together."
All picnic-goers were given planter seed packages to promote bee nutrition, and the idea of a future community garden in Mornington was a popular topic of conversation, Ms Korsten said.
The event was organised "on the smell of an oily rag", but some financial support was provided by the Dunedin City Council neighbourhood fund, she said.
Presbyterian Support Otago assisted with the events health and safety preparations.
Mornington Community Group member Glenys Needs said she was pleased the suburb now had such an event.
"I used to get a bit jealous of Northeast Valley and Caversham for having things like this," she said, laughing.
Organisers hoped the picnic would become an annual event.
